Abstract : One hundred and forty-seven cases of envenomed children under 15 years old presenting local and general symptoms without failure in vital functions (clinical grade II) or presenting serious general symptoms with failure in vital functions (clinical grade III) were collected during the summer seasons of 1993-1997. They were classified in six groups according to the use or not of antivenom, the route and the frequency of antivenom administration. The determination, by a sensitive ELISA, of blood venom concentration before and until 6 h after antivenom therapy, allowed the establishment of the venom toxicokinetic curve for each group. The intramuscular administration of antivenom did not show significant effects on venom toxicokinetic curves and on patients recovery time. However, the same amount of antivenom administered by intravenous route clear rapidly the blood free venom toxins. Also, the patient recovery time was significantly shortened. These data are in favor of intravenous application of an adequate dose of an efficient antivenom in order to treat successfully severe scorpion envenoming cases.